CVE catalog

CVE-2026-33871

Severity: High · CVSS 8.7CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Published: Mar 24, 2026, 11:00:00 PM UTC
Source: [NVD] · [CVE record]
EPSS: 1.15% · Oct 27, 2026

Netty is an asynchronous, event-driven network application framework. In versions prior to 4.1.132.Final and 4.2.10.Final, a remote user can trigger a Denial of Service (DoS) against a Netty HTTP/2 server by sending a flood of `CONTINUATION` frames. The server's lack of a limit on the number of `CONTINUATION` frames, combined with a bypass of existing size-based mitigations using zero-byte frames, allows an user to cause excessive CPU consumption with minimal bandwidth, rendering the server unresponsive. Versions 4.1.132.Final and 4.2.10.Final fix the issue.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	netty	sid	`1:4.1.48-16`	vulnerable
Debian	netty	forky	`1:4.1.48-16`	vulnerable
Debian	netty	trixie	`1:4.1.48-10+deb13u1`	vulnerable
Debian	netty	trixie-security	`1:4.1.48-10+deb13u1`	vulnerable
Debian	netty	bookworm	`1:4.1.48-7+deb12u2`	vulnerable
Debian	netty	bookworm-security	`1:4.1.48-7+deb12u2`	vulnerable
Cpe	netty	Not reported	Not reported	vulnerable
Cpe	netty	Not reported	`4.1.132`	fixed
Cpe	netty	Not reported	`4.2.10`	fixed
Cpe	netty	Not reported	`4.2.10`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	netty	source	sid	`(unfixed)`	not yet assigned	Not reported	[1132230]
Debian	netty	source	forky	`(unfixed)`	not yet assigned	Not reported	[1132230]
Debian	netty	source	trixie	`(unfixed)`	not yet assigned	Not reported	[1132230]
Debian	netty	source	bookworm	`(unfixed)`	not yet assigned	Not reported	[1132230]
Cpe	netty	cpe	Not reported	`4.1.132`	Not reported	Not reported	Not reported
Cpe	netty	cpe	Not reported	`4.2.10`	Not reported	Not reported	Not reported
Cpe	netty	cpe	Not reported	`4.2.10`	Not reported	NVD-CVE-2026-33871	Not reported

[Debian bug #1132230]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[libnetty-java]Affected
Source package: [netty]
Details (4)
- 1:4.1.48-7+deb12u2 · all · bookworm
  Affected
  nvd · netty · debian · bookworm; nvd · netty · debian · 12
- 1:4.1.48-7+deb12u2 · all · bookworm
  Affected
  nvd · netty · debian · bookworm; nvd · netty · debian · 12
- 1:4.1.48-7+deb12u2 · all · bookworm-security
  Affected
  nvd · netty · debian · bookworm; nvd · netty · debian · 12
- 1:4.1.48-7+deb12u2 · all · bookworm-security
  Affected
  nvd · netty · debian · bookworm; nvd · netty · debian · 12

[Debian 13 (Trixie)]

[libnetty-java]Affected
Source package: [netty]
Details (4)
- 1:4.1.48-10+deb13u1 · all · trixie
  Affected
  nvd · netty · debian · 13
- 1:4.1.48-10+deb13u1 · all · trixie
  Affected
  nvd · netty · debian · 13
- 1:4.1.48-10+deb13u1 · all · trixie-security
  Affected
  nvd · netty · debian · 13
- 1:4.1.48-10+deb13u1 · all · trixie-security
  Affected
  nvd · netty · debian · 13

Observed: Oct 27, 2026, 8:03:05 AM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]